This is even as the commission also issued warning letters to some others.

Mr. Tony Ojobo, NCC Director of Public Affairs in a statement issued in Abuja, noted that was only the first phase of investigation and the commission has also begun the second phase of investigation on masking activities by telecom operators.

Call masking is the act of concealing international calls coming into a country and presenting them as local in order to make profits from the difference in prices between local and international calls.

“The NCC has recently been inundated with complaints from service providers and consumers regarding the high incidence of call masking , call refiling and SIM boxing,” the statement said.

“Generally, the practice complained of involves disguising international calls as local calls in order to profit from price differentials between international and local calls.

“Apart from the resultant loss of revenue by service providers , the practice also has some negative security implications . Following a painstaking investigation process , which included collaboration with the Office of the National Security Adviser and the Department of State Services , the commission has imposed a range of sanctions on licensees involved in the fraudulent practice.”

“The commission is pleased to note that the incidence of call masking has significantly reduced since it commenced a multi-faceted approach to address the menace.

“The commission hereby informs all stakeholders that the actions so far taken are just the first stage of the exercise. The second stage , which has now commenced, will focus on the Mobile Network Operators and other persons involved in SIM boxing.

“The aim of the commission is to completely stamp out the fraudulent practice in the overall interest of all Nigerians. Accordingly, every service provider that has been sanctioned still has an opportunity to correct the identified anomalies and satisfy the commission that it should be allowed to continue to operate in Nigeria.”

The interconnect clearing house licence issued to Medallion Communications Limited was suspended for a period of 90 days while Interconnect Clearinghouse Nigeria Limited, got s strong warning.

Information Connectivity Solutions Limited and Solid Interconnectivity Services Limited were disconnected from all networks until they regularise operations, and warning letters were issued to Exchange Telecoms Limited , NiconnX Limited and Breeze Micro Limited , cautioning them against engaging in the fraudulent practice.

The NCC statement further revealed that over 750,000 numbers assigned to several Private Network Links and Local Exchange Operator licensees, were barred for masking activity.